Feb 12, 2012

All bilingual children – regardless of the languages they speak – show cognitive advantages over their English-only peers, although they may experience weakness in areas like vocabulary acquisition, says a new study by York University researchers.

The study, published today in the journal Child Development, examined the effects of specific language pairings on children’s verbal and non-verbal development, taking into account language similarities, cultural background and educational experiences.

Researchers compared more than 100 six-year-old monolingual and bilingual children (English monolinguals, Chinese-English bilinguals, French-English bilinguals and Spanish-English bilinguals), measuring their verbal and non-verbal cognitive development. The children were all public school students from the Greater Toronto Area and of similar socio-economic background.

The study reports that bilingual children differ from each other and from monolingual children in how they develop language and cognitive skills through the early school years. Children who grow up speaking two languages generally have slower language acquisition in each language than children raised speaking just one language. However, they have better “metalinguistic” development that gives them a deeper understanding of the structure of language, a skill that’s important for literacy. They also perform better on tests of non-verbal executive control, which measure the ability to focus attention where necessary without being distracted, and to shift attention when required.

“Our research shows that it doesn’t matter what the other language is – all bilingual children have an equal advantage over monolinguals in terms of non-verbal cognitive control,” says study co-author Ellen Bialystok, DistinguishedResearch Professor in York’s Department of Psychology, Faculty of Health.

Study co-author Ellen Bialystok

“People always ask if the languages themselves matter – and now we can definitively say, ‘no.’”

In terms of language acquisition, however, the study shows that some types of bilingualism – particularly where the languages are similar in origin – may have slight advantages over others. For example, Spanish-English bilinguals outperformed Chinese-English bilinguals and monolinguals on a test of English phonological awareness.

“There is really no generalized verbal outcome of bilingualism,” says Bialystok. “In terms of the language consequences of bilingualism, we found it matters very much what the other language is, what language is used in school and likely other factors as well,” she says.

Even though bilingual children may be somewhat slower in learning the vocabulary of each of their languages, Bialystok emphasizes that the benefits of speaking more than one language far outweigh any drawbacks. In previous studies, she and other researchers established that bilingualism postpones symptoms of dementia such as Alzheimer’s disease.

“The benefits of bilingualism are evident in every stage of life, from early childhood through to one’s senior years. If children are in a position to learn and speak another language, parents should definitely do everything to encourage that,” she says.

The study, “Bilingual Effects on Cognitive and Linguistic Development: Role of Language, Cultural Background and Education”, is co-authored by Raluca Barac, a PhD student in York’s Faculty of Health. The research is supported by the US National Institutes of Health.